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NDT Advance Access originally published online on March 10, 2008
Nephrology Dialysis Transplantation 2008 23(8):2647-2652; doi:10.1093/ndt/gfn065
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© The Author [2008]. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org


Outcomes of a provincial home haemodialysis programme—a two-year experience: establishing benchmarks for programme evaluation

Paul Komenda1,2,3, Michael Copland1,2, Lee Er2, Ognjenka Djurdjev2 and Adeera Levin1,2

1 Division of Nephrology, University of British Columbia 2 British Columbia Renal Agency Vancouver, British Columbia 3 Section of Nephrology, University of Manitoba, Winnipeg, Manitoba, Canada

Correspondence and offprint requests to: Paul Komenda, St. Boniface General Hospital, BG 007, 409 Tache Avenue, Winnipeg, Manitoba R2H 2A6, Canada. Fax: +1-204-233-2770; E-mail: paulkomenda{at}yahoo.com



   Abstract
Top
 Abstract
Introduction
 Methods
 Results
 Discussion
 References
 
Introduction. The province of British Columbia has the only coordinated provincial programme for home-based haemodialysis (HHD) in Canada. The centrally coordinated and locally administered programme was initiated in 2002 as a pilot project, and was firmly established with secured funding in 2004. HHD programmes have reported successful outcomes with respect to patients’ well-being, haemodynamic stability and improvement of clinical and biochemical parameters in small selected groups of patients.

Methods. This report describes the 2-year outcomes of a provincial programme, in which more liberal criteria for patient selection have been applied, and multiple sites have trained and managed the patients over a large geographic area. As a ‘newer’ modality, it is important to review outcomes objectively so as to determine the true value of this home-based programme as an alternative to other home-based therapies such as peritoneal dialysis.

Results. One hundred and five patients who completed training and commenced home therapy between April 2004 and March 2006 were followed, for a total of 163.23 patient-years (PY). The average age was 52; 71% were male and the majority (58%) were Caucasian. Mean biochemical and clinical parameters were all within provincial and national target ranges at baseline and at the time of study follow-up cessation. Overall, 34 individual patients required hospital admission and 95% of the cohort required at least one in-centre run after training was completed (0.5 hospital admissions and 11 in-centre run per PY of HHD delivered). One- and 2-year technique survivals were 81% and 61% respectively, which were 85% and 74% when censored for transplantation. We were unable to demonstrate any significant predictors of technique survival using demographic, biochemical or other variables.

Conclusion. This is the first report of HHD programme technique survival in a large provincial cohort. The 2-year technique survival of this cohort is comparable to reports of technique survival in peritoneal dialysis. These data can be used to benchmark programmes, and to foster further research to determine factors that may improve HHD technique survival.

Keywords: benchmarks; home haemodialysis; patient selection; programme evaluation; technique survival



   Introduction
Top
 Abstract
 Introduction
Methods
 Results
 Discussion
 References
 
Home haemodialysis (HHD) has been established as a safe, effective therapy for renal replacement therapy (RRT) [1–3]. A growing body of literature has demonstrated improvements in several clinical [1,4–9] and quality of life [10–14] parameters for patients on HHD over conventional haemodialysis. Randomized trials with nocturnal HHD compared with conventional HHD are ongoing [15] and a recently published study has confirmed this observational data with regard to improvements in left ventricular mass and quality of life [16].

Several studies have shown HHD to be at least cost neutral compared with other RRT modalities [17–20]. At least one formal economic analysis has shown nocturnal HHD to have significant advantages when cost and quality of life are considered together [14]. Despite these findings, however, HHD still requires large upfront costs for administration and training of patients, the purchase of new machines and the renovation of patients’ homes [21]. When all of these ‘true’ costs are taken into account, savings may not be as substantial as originally thought [22]. Irrespective of that, the clinical benefits described by numerous authors have led to increasing uptake of this modality as a choice in several provinces, and countries.

The majority of the literature on HHD to date has come from relatively few centres with a growing amount of experience with the modality. Study populations have been therefore small, and sometimes pre-selected, for certain criteria. These factors have made it challenging for most programmes to be able to report meaningful outcomes data.

British Columbia (BC) has one of the largest HHD programmes in North America. It is a centrally administered programme that operates out of multiple sites throughout the province. This programme is unique in that it has potentially more liberal admission criteria than other programmes, was not established as a pilot or study cohort and included multiple training sites across diverse geography. Thus, this population may be of value for examining technique survival and complications, such as hospitalizations, in a real-world setting. In this study, we hypothesized that there would be technique survival superior to peritoneal dialysis, and that demographic or unifying comorbid features of patients would be identified that would predict outcomes on HHD.

As a new renal replacement modality, in a publicly funded system, it is important to review outcomes objectively. The purpose of this report is to describe selected 2-year outcomes of a provincial, multi-centre HHD programme so that both positive and negative outcomes and their predictors can present better decision making in selecting patients to receive this dialysis modality, and serve as a benchmark for quality improvement initiatives as well as for other programmes.



   Methods
Top
 Abstract
 Introduction
 Methods
Results
 Discussion
 References
 
Patient selection
All patients who commenced training for HHD in BC between April 2004 and March 2006 were included in the analysis. Patients are considered candidates for HHD in BC if they express interest in the modality, speak and understand English and are deemed medically and psychosocially stable (by their training site's nephrologist in charge of HHD) to do this modality. Patients are excluded if they had a planned live donor kidney transplant within 6 months of initiation of training. All patients in the province of BC who are receiving maintenance dialysis or followed in CKD clinics have received two separate mail-out surveys in addition to follow-up phone calls to gauge interest and perceive potential barriers to them doing HHD [23]. In addition, all patients in BC's registered CKD clinics are shown a video on HHD and oriented to this modality as a viable option for receiving their RRT as part of routine clinical practice.

Ethics standards for this study were obtained from the research ethics board at the University of British Columbia, in Vancouver, BC. Data were obtained from prospectively collected information stored in the Provincial Record and Outcome Management Information System (PROMIS).

Descriptive variables
Key demographic variables and comorbidities were collected on each patient at their start date to characterize the cohort. Variables included age, sex, dialysis type [nocturnal haemodialysis (5–6 nights a week for 6–8 h), short daily dialysis (5–6 days a week for 2–3 h) or conventional three times weekly dialysis (3 days a week for 4 h) at home] at commencement of HHD and at the time of study termination in addition to the duration of dialysis prior to HHD initiation (i.e. dialysis vintage). Comorbidities collected included the presence of diabetes and documented cardiovascular disease (CVD). CVD was defined by prior myocardial infarction (MI), angina, atrial fibrillation, cerebrovascular accident (CVA), valvular disease, peripheral vascular disease (PVD), left ventricular hypertrophy (LVH), prior coronary artery bypass grafting (CABG) or congestive heart failure (CHF). Selected laboratory parameters from patient's most recent bloodwork at HHD commencement and at study termination were collected including haemoglobin, parathyroid hormone (PTH), phosphate and albumin.

Key outcomes
Patients included in this study were followed prospectively from their start date of HHD (defined as dialyzing at home, not start of training). The key ‘programme’ outcomes included technique survival, hospitalizations (all causes) and number of in-facility runs required per patient.

Statistical analysis
Descriptive statistics for baseline categorical variables are reported using percentages, while continuous variables are reported in mean with standard deviation or median with interquartile range (IQR) depending on the underlying distribution. Our primary outcomes are reported in raw numbers and as a rate [per patient-year (PY) of HHD delivered] for number of hospitalizations, length of stay and number of in-centre runs. For technique survival on HHD we constructed three different Kaplan–Meier curves, one including all reasons for failing the modality, one censored on HHD patients receiving a transplant and the third censoring for patients receiving a transplant or death.

Cox proportional hazard modelling was used to determine the predictors for technique failure on the first two of the above scenarios. The third scenario (technique survival censored for transplant or death) could not be analysed appropriately given small numbers. Variables of interest for predicting outcomes were age, sex, ethnicity, training site size (two largest sites versus all other smaller sites), prior dialysis vintage, presence of CVD and diabetes.



   Results
Top
 Abstract
 Introduction
 Methods
 Results
Discussion
 References
 
Study cohort
The derivation of our study cohort is described in Figure 1. Of the 113 patients who began training, a total of 105 patients who commenced HHD (at home) in the specified time period were followed up until 31 March 2007. The follow-up period ranges between 1 and 3 years depending on the start date, but in total we accrued 163.23 PY of exposure.


Figure 1
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  		Fig. 1 Derivation of study cohort.

 
Demographics
Table 1 describes our HHD study cohort demographically for both the entire programme and stratified by technique survival <1 year, 1–2 years and >2 years, with respect to demographics, clinical and laboratory characteristics. The patients were on average 52 years of age, predominantly male (71%), and the majority were Caucasian (58%). Importantly, 40% had some evidence of CVD, and 25% were diabetic. Patients on average had been on dialysis for 30 months prior to commencing HHD. Seventy percent perform nocturnal haemodialysis, 19% perform short daily and 11% of the cohort perform conventional dialysis (thrice weekly) at home.


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  		Table 1 Demographic description of the programme

 
The cohort was within contemporary local, national and KDOQI targets for haemoglobin, PTH, PO4 and albumin both at HHD initiation and at the time of study follow-up termination.

Technique survival
Technique survival on HHD was analysed in three different ways. A total of 37 patients dropped out of the HHD programme during the period of study. Stated reasons for discontinuation of HHD included transplantation (13), death (14), inadequate social support (2), medical reasons not otherwise specified (2), dialysis withdrawal (1), moving out of the province (1), inadequate dialysis at home (2) and unspecified (2). Figure 2 shows a Kaplan–Meier survival curve for technique survival including all reasons for failure. This analysis shows that the estimated probability of technique survival at 1- and 2-year are 81% (95% CI: 74–89%) and 61% (95% CI: 51–72%) respectively. Figure 3 shows the same analysis censoring for transplantation as a reason for technique failure that yielded 1- and 2-year survivals of 85% (95% CI: 77–92%) and 74% (95% CI: 65–84%). Figure 4 censors for both death and transplantation.


Figure 2
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  		Fig. 2 Home haemodialysis technique survival (all reasons).

 

Figure 3
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  		Fig. 3 Home haemodialysis technique survival (censored on transplant).

 

Figure 4
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  		Fig. 4 Home haemodialysis technique survival (censored on transplant and death).

 
Table 1 described the characteristics of those who survived 1 versus 2 versus >2 years on the programme. Of interest is that those with the shortest technique survival tended to be older (60 versus 52 years old), had more CVD (55% versus 40% overall) and had been on dialysis for a shorter time period (19 versus 30 months). However, our analyses were not able to identify any significant predictors of technique survival in either scenario 1 (all causes for technique failure) or 2 (censoring for transplantation), see Tables 2 and 3 for details.


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  		Table 2 Predictors of technique survival (scenario 1—all causes)

 

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  		Table 3 Predictors of technique survival (scenario 2—censored for transplantation)

 
Hospitalizations and in-centre runs
Table 4 describes the total hospitalizations and in-centre runs. In 163.23 PY on HHD, accounted for by 105 patients, 34 (32%) individual patients required hospital admission and 95 (90%) of the unique patients required at least one in-centre dialysis run. Thus, the rate of hospital admissions is 0.5/PY, and that of in-centre runs is 11/PY of HHD delivered.


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  		Table 4 Hospitalizations and in-centre runs

 


   Discussion
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
References
 
This report provides an in-depth description of 2-year outcomes in one of the largest HHD cohorts in North America. In a real-world practice using liberal patient selection criteria, the likelihoods of a patient stay on HHD programme at 1 and 2 years after commencing HHD are 85% and 74% (censoring for transplantation). The programme hospital admission rates are low and required about 0.5 hospital admissions, but importantly, we describe 11 in-centre dialysis runs per PY. These observed outcomes in a provincially administered, multi-centre setting may serve as a starting point for this programme and others to benchmark evaluation of outcomes, review criteria for patient selection, and develop programmes to improve these outcomes. This is the first report to our knowledge to assess, from a programmatic perspective, these outcomes. They are comparable to local peritoneal dialysis outcomes, another home-based technique.

The majority of the current literature on HHD programmes has been largely focused on single centre observational experiences answering discrete questions about the safety [2], costs [17–19], quality of life impacts [10–14,24] and purported physiologic benefits of the modality [1,4–7,9,25]. As more robust data accumulates on the benefits of HHD, including RCT data [16], it will be increasingly important for programmes growing in size and scope to develop protocols and guidelines by which to select patients most likely to benefit from the treatment, without excess use of resources. This report captures some important outcomes in a large cohort of patients that should serve as a useful starting point for programmes to evaluate the overall value and total costs of technique survival, hospitalizations and in-centre runs for this cohort.

We chose technique survival as one of our primary outcomes of interest for a number of reasons. HHD does share many features with peritoneal dialysis in terms of patient independence and psychosocial impacts. Peritoneal dialysis patients are more likely to be younger, more educated and have less comorbid conditions than conventional HD patients [26]. Given that PD and HHD programmes may be more similar in size and patient characteristics than their conventional HD counterparts, it may be useful to evaluate HHD programme quality metrics in a similar fashion [27]. The fact that our outcomes are similar to that of published and our own PD survival rates bolsters this argument. One large Canadian study has reported crude PD technique survival rates of 154/1000 PY from 1981 to 1997 [28]. These same investigators found significant differences for technique survival rates across centres, rendering this outcome a potential indicator of programme quality. The National Kidney Foudation/Kidney Dialysis Outcomes Quality Initiative guidelines (2006) suggest monitoring for technique survival and hospitalizations as part of an overarching strategy for dialysis quality improvement initiatives. Technique survival is important in terms of allocating resources for treatment programmes that require substantial infrastructure. Understanding the costs of supporting this cohort is valuable in health care planning.

Our study has several admitted limitations. This is not a randomized control trial, and we did not compare a comparable matched control group who chose not to enrol in the HHD programme. However, as it was not the purpose of this study to evaluate the efficacy of this modality against other forms of conventional RRT, this is a relative limitation. This cohort is the first cohort to be trained in BC; it thus may not be representative of cohorts in the future. Furthermore, the thresholds of the programmes for admission to hospital and readmission for in-centre runs are not protocolized: as the first group of trained patients, it is conceivable that the reasons for admission and in-centre runs will be modified over time. Nonetheless, these remain reasonable parameters to evaluate both for our own programme and as parameters for any new programme of this size.

The sample size is relatively small, though larger than other published reports. The duration of the follow-up is also relatively short, but given that the majority of patients were ‘seasoned’ dialysis patients (average of 30 months prior to programme start); this should be an adequate follow-up from which to make some conclusions. The need to identify subgroups that are at risk to prematurely fail the modality is important given the resource intensity of initiation of this modality. Our study was unable to identify consistent variables that would discriminate between patients at risk of technique failure and those who were successful. There are several potential explanations for this. First, despite having over 163 PY of follow-up, relatively few of our patients left the programme over the 2 years of our study; thus the sample size of those who failed was relatively small. A longer duration of follow-up and more patients/higher PY of follow-up will be necessary to identify clinically important predictors of technique failure. Plans are currently underway to establish a national multi-centre HHD collaborative to facilitate the development of a large cohort that would be able to address this and other important questions.

Secondly, due to the relatively small population, there were a finite number of variables we could include in the model and still maintain statistical validity. We included many potential variables that we believe could lead to technique failure on HHD, but the sample size restricted our ability to truly test the model in a robust manner. Thirdly, our HHD cohort consists of patients with a prior dialysis vintage of about 30 months. Hence, this cohort is possibly biased in favour of ‘survivors’ on dialysis to begin with. Our limited numbers unfortunately did not allow us to perform sub-analysis on patients new to dialysis versus those with a longer vintage while maintaining statistical validity.

Our analysis does provide useful insights into the selection of patients into our provincial programme. Despite our pre-defined selection criteria, a significant percentage (35%) of our patients left the programme because they received a kidney transplant. This is not truly a ‘treatment failure’, but rather a signal to programmes to ensure close communication with transplant coordinators so that those patients close to their potential transplant dates may not be formally assessed and integrated into the HHD programme. Aside from exceptional cases, the benefits of short-term HHD (<1 year) do not likely justify the intense upfront resource inputs needed to train and equip a patient for this modality. The provincial group is currently exploring the logistics of facility-based intensive dialysis programmes to allow for pre-transplant patients to derive the benefits of more intensive HD modalities without utilizing the high cost initiation resources (such as training and home renovations).

We have presented here a description of 2-year outcomes for one of the largest geographically dispersed HHD cohorts in North America. These outcomes will hopefully be useful to this and other programmes regarding benchmarking of key outcomes including quality of care targets, continuous quality improvement initiatives and outcomes such as technique survival.

We will be working with other experienced HHD programmes to increase the cohort size, and thus our statistical power to better characterize patients who may not benefit from this modality. It is imperative to objectively evaluate and further study these cohorts of patients, so that we may maximize efficient resource use and improve patient outcomes. In an era of organ shortages for transplantation, and offering more flexible and intense HD regimens, it is important that we thoroughly reflect on all outcomes and the health resource implications of HHD programmes.

Conflict of interest statement. None declared.



   References
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 

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Received for publication: 15.11.07
Accepted in revised form: 25. 1.08


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